/Engine/Plugins/Runtime/MeshModelingToolset/Source/MeshModelingTools/Public/EditMeshPolygonsTool.h
Make each selected polygroup edge follow a straight path between its endpoints
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(CallInEditor, Category=EdgeEdits, Meta=(DisplayName="Straighten", DisplayPriority=2)) void Straighten()